Years ago I had an office in Boston that looked out on the Granary Burying Ground where many prominent American heroes are buried. There one can find the gravestones for John Hancock and Samuel Adams, two signers of the Declaration of Independence, and just a few feet beyond that is Paul Revere’s marker.

But no one really knows where in this burial ground each body is buried because the stones have been moved many times—sometimes to make the grounds more picturesque and other times so lawn mowers could fit between them. And while the Granary features approximately 2,300 markers, closer to 5,000…